The present invention relates to a flyback transformer, and more particularly, to a flyback transformer with a core grounded.
A flyback transformer is generally implemented within the circuits of a display device for providing distinctive voltages required by the circuits operation of the display device. Some U.S. Patents, i.e. U.S. Pat. Nos. 5,160,872, 5,287,479, 4,144,480 and 4,475,097 may be referred in order to have an in-depth understandings of structures of the flyback transformer and functions of High Voltage output, Focus output and Screen output of the flyback transformer.
Please refer to FIGS. 1 and 2. FIG. 1 is a schematic diagram of a flyback transformer 10 according to the prior art. FIG. 2 is an exploded diagram of the flyback transformer 10 shown in FIG. 1. A flyback transformer 10 of the prior art comprises a low-voltage bobbin 12, a high-voltage bobbin 14, an upper core 16, a lower core 18, a housing 20 and a clip 22. The assembly procedure of the flyback transformer 10 comprises: first, installing a winding shaft (not shown) of the low-voltage bobbin 12 into a shaft hole (not shown) of the high-voltage bobbin 14; secondly, installing the low-voltage bobbin 12 and high-voltage bobbin 14 into the housing 20; finally, mounting the upper and lower cores 16, 18 on the low-voltage bobbin 12 by the clip 22 to form the flyback transformer 10.
Please refer to FIG. 3. FIG. 3 is an assembly diagram of the low-voltage bobbin 12, clip 22 and upper and lower cores 16, 18. The clip 22 is formed of a thicker metal wire rod, such as stainless or piano wire, subjected to surface treatment, such as galvanization or tinning and bent in a U-shape, a grounding end 24 being bent from and integral with the lower end of clip 22. And then, the grounding end 24 is mounted onto a predetermined bore of a printed substrate (not shown) for grounding the upper and lower cores 16, 18. In addition, fitting holders 28 are provided on the outer surface of low-voltage bobbin 12 as shown in FIG. 3 and a positioning fitting 26 is fitted onto the low-voltage bobbin 12 and fixed at both ends to the fitting holders 28 for positioning the grounding end 24. Nevertheless, the positioning fitting 26 really provides the grounding end 24 with high positional accuracy, it always leads to increase product cost and assembly complexity of the flyback transformer 10. So the positioning fitting 26 is not used extensively for the flyback transformer 10.
It is therefore a primary objection of the present invention to provide a flyback transformer with a core grounded to solve the above mentioned problem.
In a preferred embodiment, the present invention provides a flyback transformer comprising a core, a low-voltage bobbin and a conductive device. The core comprises an upper core and a lower core. The low-voltage bobbin comprises a skirt. The skirt has a lower opening for receiving the lower core and a grounding pin is provided on a side portion of the skirt. The conductive device comprises an U-shaped body, an input end and an output end. The U-shaped body is engaged with the side portion of the skirt. The input end is provided on one end of the U-shaped body for flexibly connecting the lower core. The output end is provided on the other end of the U-shaped body for connecting the grounding pin. The core is grounded by the way of connecting the lower core and the grounding pin through the conductive device.
These and other objectives of the present invention will no doubt become obvious to those of ordinary skill in the art after reading the following detailed description of the preferred embodiment which is illustrated in the various figures and drawings.